-Summary:
From the point of view of their mechanism of action, spironolactone, flutamide and cyproterone acetate are antagonists of the androgen receptor, while finasteride is an inhibitor of the 5-alpha-reductase enzyme, responsible for the conversion of testosterone (T) to 5-dihydrotestosterone (5-DHT), a more potent androgen because it has a greater affinity than Testosterone for its receptor.
-Development:
However, the actions of these drugs are not completely specific to the androgen receptor, since they may have other effects, as explained below.
Spironolactone is primarily an aldosterone antagonist with antiandrogenic properties; She reduces the bioavailability of testosterone by interfering with its production, increasing its metabolic clearance rate, and reducing cutaneous 5-alphareductase activity.
In addition to binding to the intracellular androgen receptor, forming a biologically inactive compound. Additionally, it has some progestogenic activity which contributes to lowering LH levels, thus attenuating its effect on steroidogenesis.
On the other hand, it degrades a cytochrome p450 cofactor, necessary for the synthesis of testosterone at the gonadal and adrenal level, in addition to increasing the levels of sex hormone-binding globulin, which decreases the levels of free testosterone.
Androgens contribute to the development of several skin diseases, such as acne, female pattern androgenetic alopecia (FAGA), hirsutism, and hidradenitis suppurativa (HS), among others.
These diseases may be associated with hyperandrogenism, although most cases occur without systemic androgenic abnormalities.
Antiandrogenic therapy is a reasonable option in this context, and spironolactone is a low-cost alternative with a good safety profile.
The recommended dose of spironolactone is 25, 50, 100 to 200 mg, depending on the case, daily. Its therapeutic effects, like the other antiandrogens described below, take variable time to manifest.
It is commonly observed that the severity and number of acne lesions are reduced in a matter of a few weeks, and the maximum effects are already reached after 3 months of use.
On the other hand, the effects on hirsutism, and even more so on androgenetic alopecia, are later, and manifest after 6 to 9 months, or more.
In particular, androgenetic alopecia may have an insufficient response, particularly in women with a strong genetic load for this condition.
The most common side effect of spironolactone used in women at the mentioned doses is breakthrough spotting, which is seen in up to half of the cases.
This also occurs in patients who are taking oral contraceptives, and is attributed to its progestogenic action.
Other side effects include mastalgia, headache, dizziness and, due to its antialdosterone effect, hyperkalemia, so it is recommended to monitor potassium levels, and in hot climates, be aware of adequate hydration and salt intake.
Spironolactone is also used in combination with other medicines to treat precocious puberty, a condition that causes boys to enter puberty too early, in girls under 8 years of age and in boys usually under 9 years of age.
Other uses of spironolactone are: myasthenia gravis (MG), a disease in which the nerves do not function correctly, heart failure, high blood pressure, edema associated with liver cirrhosis or nephrotic syndrome.
About 1% of hypertensive patients have an elevated aldosterone level, so in these cases the antihypertensive effects of spironolactone are superior to combined antihypertensive therapies; It is what is known as primary hyperaldosteronism.
Spironolactone may also be used to treat certain women with abnormal facial or body hair.
-Conclusions:
Spironolactone is a diuretic medication that is sometimes used by women to treat moderate to severe acne.
-The FDA approved spironolactone as a drug to treat high blood pressure that results from a hormonal condition called hyperaldosteronism.
Spironolactone is an oral medication that is taken once a day.
-Men are advised not to use spironolactone for acne due to side effects which include increased feminine characteristics.
-References:
Goodman, Alfred (2019). «Chapter 25 «Drugs Affecting Renal Function»». The pharmacological bases of therapeutics. Mc Graw Hill.
DOI: 10.1016/j.ad.2020.03.001.Use of spironolactone in dermatology: acne, hidradenitis suppurativa, female alopecia and hirsutism.P. Vargas-Mora et al.
-Keywords:
spironolactone and androgens, spironolactone as antiandrorigen, spironolactone and acne, spironolactone and arterial hypertension, spironolactone and primary hyperaldosteronism, spironolactone and precocious puberty, spironolactone and androgenic alopecia, hidradenitis and spironolactone, spironolactone and myasthenia gravis, spironolactone and androgen receptor, spironolactone and potassium, spironolactone and heart failure, spironolactone and hirsutism.
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